No memory card is fast enough to keep the 7DII's 10 fps rate constant when shooting in full resolution RAW format. The camera has a buffer ensuring that the maximum framerate can be held for some (short) time, no matter how fast a memory card is used, but how long the framerate can be held and how low the framerate goes when buffer is full, greatly depends on how fast the camera can write the buffercontent to the used memorycard.
The top-5 fastest cards in Camera Memory Speed's test with Canon EOS 7D Mark II
At cameramemoryspeed.com they have benchmarked a number of CompactFlash and SD-cards with the 7DII. Do you want the fastest possible card, or are you looking for a "best-value" choice? Take a look at Camera Memory Speed's measurements of flashcards with 7DII.
At Camera Memory Speed they have used a 30 MB big RAW file for their testing. Canon's RAW files vary in size (using lossless compression), and most 7DII RAW files are probably a bit smaller than the one used for this testing. So your practical output might be a bit better than these results, however no doubt that the chosen memory card is very important for the practical framerate you can get.
Yesterday Lexar introduced a new Professional 600x CompactFlash type Memory Card supporting UDMA 6. This is following similar announcements from Sandisk and others. The 7D is the first Canon camera to support this new standard. How does the first UDMA 6 cards perform in it?...
In a mini-test Rob Galbraith compares speed of the latest and fastest cards in the Canon EOS 7D and Nikon D300s. Newest cards from Lexar, Sandisk, Transcend and others are included in this little test, and used in the Canon EOS 7D there are significant speed differences.
Read the test...